My initial installation of Rockbox failed and became corrupted and I had to remove it before trying again. I wasn’t that keen at first except that Rockbox happily played files from some of my Micro SD cards that the original firmware claimed were “empty”.
However once I loaded an alternative layout (there are lots on the Rockbox site) and changed the fonts to a size I could actually read I’ve got on a lot better and I usually play from Rockbox now. I don’t use any sound adjustments and am not aware of any difference in sound with Rockbox.
The FM Radio has never worked though in Rockbox but is fine with the OF. The Clip just locks up if I try and use it but it’s not really a problem as I rarely listen to the FM Radio anyway.